Vb.net BC30451和#x9'；变量'；未声明。由于其保护级别，可能无法访问

我似乎对下面的代码有错误

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.CenterToScreen()


    If My.Computer.FileSystem.FileExists("bin\php\php.exe") Then
        Dim PHPRC As String = ""
        Dim PHP_BINARY As String = "bin\php\php.exe"
    Else
        Dim PHP_BINARY As String = "php"
    End If

    If My.Computer.FileSystem.FileExists("PocketMine-MP.phar") Then
        Dim POCKETMINE_FILE As String = "PocketMine-MP.phar"
    Else
        If My.Computer.FileSystem.FileExists("src\pocketmine\PocketMine.php") Then
            Dim POCKETMINE_FILE As String = "src\pocketmine\PocketMine.php"
        Else
            MsgBox("Couldn't find a valid PocketMine-MP installation", MsgBoxStyle.Exclamation, "PocketMine-MP")
        End If

    End If

    Process.Start("C:\Users\Damian\Desktop\Games\Pocketmine\Installer\PocketMine-MP\bin\mintty.exe", "-o Columns=88 -o Rows=32 -o AllowBlinking=0 -o FontQuality=3 -o Font='DejaVu Sans Mono' -o FontHeight=10 -o CursorType=0 -o CursorBlinks=1 -h error -t 'PocketMine-MP' -i bin/pocketmine.ico -w max" & PHP_BINARY & "" & POCKETMINE_FILE & "" & "--enable-ansi")

End Sub

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我不断地犯这个错误

BC30451未声明“PHP_二进制”。由于其保护级别，可能无法访问

BC30451未声明“POCKETMINE_文件”。由于其保护级别，可能无法访问

我做错了什么

---

（仅供参考，仅出于测试原因，它处于Form1_Load中。）

您正在调暗if语句中的两个变量，因此一旦您点击“end if”，您的变量将消失，或“超出范围”。你绝对应该对……做些研究。。。要在代码中解决这个问题，首先在子语句内部、if语句外部的顶部声明字符串。然后只需使用if语句来更改变量所包含的内容；这样，当出现流程调用时，变量不会超出范围：

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.CenterToScreen()

    Dim PHP_BINARY As String = Nothing
    Dim POCKETMINE_FILE As String = Nothing

    If My.Computer.FileSystem.FileExists("bin\php\php.exe") Then
        PHP_BINARY = "bin\php\php.exe"
    Else
        PHP_BINARY = "php"
    End If

    If My.Computer.FileSystem.FileExists("PocketMine-MP.phar") Then
        POCKETMINE_FILE = "PocketMine-MP.phar"
    Else
        If My.Computer.FileSystem.FileExists("src\pocketmine\PocketMine.php") Then
            POCKETMINE_FILE = "src\pocketmine\PocketMine.php"
        Else
            MsgBox("Couldn't find a valid PocketMine-MP installation", MsgBoxStyle.Exclamation, "PocketMine-MP")
        End If

    End If

    Process.Start("C:\Users\Damian\Desktop\Games\Pocketmine\Installer\PocketMine-MP\bin\mintty.exe", "-o Columns=88 -o Rows=32 -o AllowBlinking=0 -o FontQuality=3 -o Font='DejaVu Sans Mono' -o FontHeight=10 -o CursorType=0 -o CursorBlinks=1 -h error -t 'PocketMine-MP' -i bin/pocketmine.ico -w max" & PHP_BINARY & "" & POCKETMINE_FILE & "" & "--enable-ansi")

End Sub